Hypervelocity rocket sled systems are critical for testing advanced military technologies,yet track damage at speeds exceeding Mach 5 remains a significant challenge for system reliability and performance.In this stud...Hypervelocity rocket sled systems are critical for testing advanced military technologies,yet track damage at speeds exceeding Mach 5 remains a significant challenge for system reliability and performance.In this study,we investigated the hypervelocity impact response and protection for highstrength U71 Mn or bainitic steel used in rocket sled tracks.Flyer plate impact experiments using a two-stage light-gas gun were conducted to study the hypervelocity collision response,followed by the microstructural characterization via optical microscope,scanning electron microscopy equipped with electron backscatter diffraction to reveal underlying damage mechanisms.Then,the calibrated thermalmechanical coupled finite element simulations using the Johnson-Cook constitutive model and MieGrüneisen equation of state were carried out.Results indicated that bainitic steel exhibits superior impact resistance with predominantly smooth scratch-dominated damage due to its higher ductility.In contrast,U71 Mn suffered significant material spallation and crack propagation arising from brittle fracture mechanisms.Zinc-rich epoxy primer coatings effectively mitigated stress concentration and temperature rise in the substrate at impacting velocities below 2.4 km/s,so as to suppress the microstructural damage such as adiabatic shear bands and dynamic recrystallization.However,coating protection diminished at ultra-high-speed impacts due to the coating failure.Dimensional analysis established quantitative relationships of the gouge damage size to projectile mass,impact velocity,and material yield strength.This study provides in-depth insights into damage mechanisms in hypervelocity rail systems,demonstrating that bainitic steel combined with protective coatings can significantly enhance impact resistance and system reliability,offering valuable guidance for the design and optimization of hypervelocity testing platforms.展开更多
The increasing risk of ground pressure disasters resulting from deep well mining highlights the urgent need for advanced monitoring and early warning systems.Ground pressure monitoring,supported by microseismic techno...The increasing risk of ground pressure disasters resulting from deep well mining highlights the urgent need for advanced monitoring and early warning systems.Ground pressure monitoring,supported by microseismic technology,plays a pivotal role in ensuring mine safety by enabling real-time identifi cation and accurate classification of vibration signals such as microseismic signals,blasting signals,and noise.These classifications are critical for improving the efficacy of ground pressure monitoring systems,conducting stability analyses of deep rock masses,and implementing timely and precise roadway support measures.Such eff orts are essential for mitigating ground pressure disasters and ensuring safe mining operations.This study proposes an artificial intelligence-based automatic classification network model for mine vibration signals.Based on conventional convolutional neural networks,the proposed model further incorporates long short-term memory(LSTM)networks and attention mechanisms.The LSTM component eff ectively captures temporal correlations in time-series mining vibration data,while the attention mechanism enhances the models’ability to focus on critical features within the data.To validate the eff ectiveness of our proposed model,a dataset comprising 480,526 waveform records collected in 2022 by the microseismic monitoring system at Guangxi Shanhu Tungsten Mine was used for training,validation,and testing purposes.Results demonstrate that the proposed artifi cial intelligence-based classifi cation method achieves a higher recognition accuracy of 92.21%,significantly outperforming traditional manual classification methods.The proposed model represents a signifi cant advancement in ground pressure monitoring and disaster mitigation.展开更多
The electrocatalytic urea oxidation reaction(UOR)has emerged as an energy-efficient alternative to the traditional oxygen evolution reaction for hydrogen production,with mechanistic understanding being critical for th...The electrocatalytic urea oxidation reaction(UOR)has emerged as an energy-efficient alternative to the traditional oxygen evolution reaction for hydrogen production,with mechanistic understanding being critical for the rational design of catalysts.This review systematically summarizes recent advances in in situ characterization techniques for elucidating the dynamic reaction mechanisms of UOR.Studies reveal that phase transitions,valence state migration,and electronic structure evolution of catalysts under operational conditions are key factors governing activity and stability.Techniques such as in situ X-ray diffraction,X-ray absorption spectroscopy,Raman spectroscopy,and Fourier-transform infrared spectroscopy enable real-time monitoring of catalyst reconstruction,intermediate evolution,and interfacial adsorption behavior,overcoming the environmental deviations inherent in conventional ex situ characterization.When combined with theoretical calculations,these methods provide direct evidence for identifying active-site configurations,reaction pathways,and rate-determining steps.In addition,special emphasis is placed on multimodal in situ strategies for deciphering synergistic effects in nickel-based catalysts,while current challenges,including non-alkaline systems,real wastewater environments,and multi-metal cooperation mechanisms,are critically discussed.Future research should focus on developing novel in situ approaches for complex systems and establishing a mutually reinforcing framework integrating theoretical prediction and experimental validation,thereby advancing UOR catalyst design from empirical exploration to mechanism-guided optimization.展开更多
Objective:To analyze the risk of osteoporosis among middle-aged men in the cold regions of China(Heilongjiang Province)and provide theoretical support for the early identification of high-risk populations.Methods:Bone...Objective:To analyze the risk of osteoporosis among middle-aged men in the cold regions of China(Heilongjiang Province)and provide theoretical support for the early identification of high-risk populations.Methods:Bone mineral density(BMD)data were collected from male subjects aged 50-65 who met the inclusion criteria at the physical examination center of a hospital in Harbin between August to December 2022.General clinical data and dietary information were obtained through face-to-face interviews using a dietary questionnaire survey.Results:The prevalence of osteoporosis and osteopenia was 14.38%and 52.06%,respectively,while normal bone mass accounted for 33.56%.Significant differences were observed among groups in smoking habits,sunlight exposure,exercise levels,and dietary patterns at each bone mass level.The BMD of the lumbar spine,femoral neck,and hip showed a negative correlation with the Dietary Inflammatory Index(DII)score.Multivariate logistic regression analysis revealed that smoking and a diet high in oil and salt were positively associated with the risk of osteoporosis.A pro-inflammatory diet was also positively correlated with osteoporosis risk,with individuals in this group being 7.723 times more likely to develop osteoporosis compared to those in the anti-inflammatory diet group.Conclusion:The high prevalence of osteoporosis and osteopenia observed in this study highlighted that osteoporosis is a significant and pressing issue among middle-aged men.Smoking,limited sunlight exposure,reduced physical activity,diets high in oil and salt,and pro-inflammatory diets were identified as major risk factors for bone loss.These factors are closely linked to the geography,climate,and cultural practices of cold regions in China.Primary healthcare in this region should focus on the screening and prevention of osteoporosis in middle-aged men by promoting smoking cessation,increased sunlight exposure,adequate vitamin D supplementation,regular physical activity,and adherence to a healthy diet to maintain bone health.展开更多
Hepatitis B virus(HBV)infection is a global health concern.The current sequen-tial endpoints for the treatment of HBV infection include viral suppression,hepatitis B e antigen(HBeAg)seroconversion,functional cure,and ...Hepatitis B virus(HBV)infection is a global health concern.The current sequen-tial endpoints for the treatment of HBV infection include viral suppression,hepatitis B e antigen(HBeAg)seroconversion,functional cure,and covalently closed circular DNA(cccDNA)clearance.Serum hepatitis B core-related antigen(HBcrAg)is an emerging HBV marker comprising three components:HBeAg,hepatitis B core antigen,and p22cr.It responds well to the transcriptional activity of cccDNA in the patient's liver and is a promising alternative marker for serolo-gical testing.There is a strong correlation,and a decrease in its level corresponds to sustained viral suppression.In patients with chronic hepatitis B(CHB),serum HBcrAg levels are good predictors of HBeAg seroconversion(both spontaneous and after antiviral therapy),particularly in HBeAg-positive patients.Both low baseline HBcrAg levels and decreasing levels early in antiviral therapy favored HBsAg seroconversion,which may serve as a good surrogate option for treatment endpoints.In this review,we summarize the role of serum HBcrAg in the treat-ment of CHB.Therefore,long-term continuous monitoring of serum HBcrAg levels contributes to the clinical management of patients with CHB and optimizes the choice of treatment regimen,making it a promising marker for monitoring HBV cure.展开更多
Cropland is persistently affected by soil loss by water erosion in China,which causes economic loss and threatens soil health.Integrating crop switching and improved management provides a promising strategy for contro...Cropland is persistently affected by soil loss by water erosion in China,which causes economic loss and threatens soil health.Integrating crop switching and improved management provides a promising strategy for controlling soil loss by water erosion in cropland and promoting sustainable agriculture.However,optimizing crop composition with fewer inputs involves balancing agricultural resource use with environmental costs.Aiming to explore the potential of crop switching as a strategy for mitigating soil erosion in cropland,we develop a spatial optimization model that redistributes the sown areas of different crops in each prefecture-level city based on existing resource availability.Our findings gained from our simulations show that crop switching in China alone can reduce total soil erosion in cropland by an estimated 13%.Furthermore,combining crop switching with improved agricultural management practices can further reduce soil erosion in cropland by an estimated 25%.Cereals including maize,wheat,and rice demonstrate significant potential for reducing soil erosion in cropland.Shifting major maize-producing areas northward could result in a substantial decrease in soil erosion,ranging from 10% to 19% of historical soil erosion in cropland.These results offer implications for formulating regional strategy in mitigating soil erosion challenges in China while maximizing the benefits from existing agricultural resource.展开更多
Bubbles are prevalent defects on the oxidized surfaces of ultra-high temperature carbides,compromis-ing structural stability and oxidation resistance.Despite their significance,the formation mechanisms and microstruct...Bubbles are prevalent defects on the oxidized surfaces of ultra-high temperature carbides,compromis-ing structural stability and oxidation resistance.Despite their significance,the formation mechanisms and microstructural evolution of bubbles during ultra-high temperature oxidation remain inadequately understood.To address this gap,the bubble behaviors of multicomponent carbides,including(Hf,Ti)C,(Hf,Zr,Ti)C,(Hf,Zr,Ti,Ta)C,and(Hf,Zr,Ti,Nb)C,were investigated under oxidation conditions at 2500℃.The roles of various elements were elucidated through first-principles calculations.Results show that the for-mation of a dense composite oxide layer is essential for bubble generation,with the release of gaseous products serving as the primary driving force.The microstructure of the bubbles is influenced by the ma-trix composition.The addition of Ti,Ta,and Nb significantly lowers the surface energy of the shell oxides,providing preferential nucleation sites for bubbles.The progressive oxidation of Ti leads to the formation of a“TiO_(2)-TiO-HfO_(2)”multilayerstructureat thebubbletop,which evolvesintoadendriticstructurewith prolonged oxidation.Ta and Nb further modulate the size and number of bubbles by altering the compo-sition and surface energy of the shell oxides.展开更多
BACKGROUND The incidence of hypertriglyceridemic acute pancreatitis(HTG-AP)has increased yearly,but updated population-based estimates on the incidence of HTG-AP are lacking.Reducing serum triglyceride(TG)levels quick...BACKGROUND The incidence of hypertriglyceridemic acute pancreatitis(HTG-AP)has increased yearly,but updated population-based estimates on the incidence of HTG-AP are lacking.Reducing serum triglyceride(TG)levels quickly is crucial in the early treatment of HTG-AP.Decreased serum TG levels are treated by non-invasive methods,which include anti-lipidemic agents,heparin,low-molecular weight heparin,and insulin,and invasive methods,such as blood purification including hemoperfusion(HP),plasmapheresis,and continuous renal replacement therapy.However,authoritative guidelines have not been established.Early selection of appropriate treatment is important and beneficial in controlling the development of HTG-AP.AIM To evaluate the effect between patients treated with intravenous insulin(INS)and HP to guide clinical treatment.METHODS We retrospectively reviewed 371 patients with HTG-AP enrolled in the Department of Fujian Provincial Hospital form April 2012 to March 2021.The inpatient medical and radiologic records were reviewed to determine clinical features,severity,complications,mortality,recurrence rate,and treatment.Multivariate logistic regression analyses were used to analyze risk factors for severe HTG-AP.Propensity score matching was used to compare the clinical outcomes of INS and HP.RESULTS A total of 371 patients met the HTG-AP criteria.The incidence of HTG-AP was increased by approximately 2.6 times during the 10 years(8.4%in April 2012-March 2013 and 22.3%in April 2020-March 2021).The highest incidence rate of acute pancreatitis was observed for men in the age group of 30-39 years.The amylase level was elevated in 80.1%of patients but was only three times the normal value in 46.9%of patients.The frequency of severe acute pancreatitis(26.9%),organ failure(31.5%),rate of recurrence(32.9%),and mortality(3.0%)of HTG-AP was high.Improved Marshall score,modified computed tomography severity index score,baseline TG,baseline amylase,C-reactive protein(CRP),albumin,aspartate aminotransferase,low-density lipoprotein cholesterol,urea nitrogen,creatinine,calcium,hemoglobin,free triiodothyronine,admission to intensive care unit,and mortality were significantly different between patients with different grades of severity(P<0.050).Multivariate logistic regression analysis confirmed that high CRP[P=0.005,odds ratio(OR)=1.011,95%CI:1.003-1.019],low calcium(P=0.003,OR=0.016,95%CI:0.001-0.239),and low albumin(P=0.023,OR=0.821,95%CI:0.693-0.973)were risk factors of severe HTG-AP.After propensity score matching adjusted by sex,age,severity of HTG-AP,and baseline TG,the serum TG significantly decreased in patients treated with INS(P<0.000)and HP(P<0.000)within 48 h.However,the clearance rate of TG(57.24±33.70%vs 56.38±33.61%,P=0.927)and length of stay(13.04±7.92 d vs 12.35±6.40 d,P=0.730)did not differ between the two groups.CONCLUSION The incidence of HTG-AP exhibited a significant increase,remarkable severity,and recurrent trend.Patients with mild and moderately severe acute pancreatitis can be treated effectively with INS safely and effectively without HP.展开更多
AIM:To investigate the relationship between human papillomavirus(HPV)infection and concurrent esophagus and gastric cardia cancer from the same patient(CC)and examine the significance of P16 INK4A protein expression.M...AIM:To investigate the relationship between human papillomavirus(HPV)infection and concurrent esophagus and gastric cardia cancer from the same patient(CC)and examine the significance of P16 INK4A protein expression.METHODS:Polymerase chain reaction was used to detect the presence of HPV type16(HPV16).The expression of P16 INK4A protein was detected using immunohistochemistry.RESULTS:Among the CC specimens,HPV16-DNA was found in eight cases of esophageal squamous cell carcinoma(ESCC)and five cases of gastric cardia adenocarcinoma(GCA),respectively(47%vs 29%),and two of both ESCC and GCA.P16 INK4A was highly expressed in both ESCC and GCA.In the HPV-associated positive CC,higher P16 INK4A expression was observed in the GCA than in the ESCC(75%vs 25%,P<0.05).CONCLUSION:HPV16 as a correlated risk factor may play an important role in the development of ESCC and GCA.P16 INK4A may be a screening index in the HPVassociated carcinoma of gastric cardia.展开更多
The basal levels of magnesium and copper in rat brain and flowering plum fruit dialysates, and the background concentration of calcium in pea dialysates have been determined with sensitive spectroscopic techniques inc...The basal levels of magnesium and copper in rat brain and flowering plum fruit dialysates, and the background concentration of calcium in pea dialysates have been determined with sensitive spectroscopic techniques including atomic absorption spectrometry and spectrophotometry based on amino G acid chlorophosphonazo. It is found that the magnesium level in flowering plum fruit dialysates is much lower than that in rat brain dialysates, indicating a considerable composition difference present between a plant dialysate and an animal one.展开更多
Objective To investigate the expression of miRNA-140 in chondrocytes and synovial fluid of osteoarthritis(OA) patients, and explore the relationship between the miRNA-140 expression and OA severity. Methods This study...Objective To investigate the expression of miRNA-140 in chondrocytes and synovial fluid of osteoarthritis(OA) patients, and explore the relationship between the miRNA-140 expression and OA severity. Methods This study enrolled 30 OA patients who underwent total knee arthroplasty for chondrocytes sampling and 30 OA patients who underwent intra-articular injection for synovial fluid sampling. All OA patients were grouped into mild [Kellgren and Lawrence(KL) grade 1-2], moderate(KL grade 3) and severe(KL grade 4), with 10 in each subgroups for each sampling purposes. 7 non-OA patients and 10 patients with knee injury were collected for cartilage and synovial fluid sampling respectively as control groups. Chondrocytes were isolated from the cartilage tissue and cultured in vitro. Quantitative real time PCR for miRNA-140 in chondrocytes and synovial fluid were performed, and the U6 sn RNA was used as internal control. The expression difference of miRNA-140 among groups and correlation between the expression and the KL grade of OA were analysed using one-way ANOVA and Spearman test respectively. Results The expression of miRNA-140 in chondrocytes of knees in OA patients was reduced than that in normal knees, and the between-group difference was statistically significant(F=305.464, P<0.001). miRNA-140 could be detected in synovial fluid of both normal knees and OA knees, its relative expression level was reduced in synovial fluid of OA group compared with normal group, and the between-group difference was statistically significant as well(F=314.245, P<0.001). The relative expression level of miRNA-140 in both chondrocytes and synovial fluid were negatively correlated with the KL grade of OA(r=-0.969, P<0.001; r=-0.970, P<0.001). Conclusion miRNA-140 could be detected in chondrocytes and synovial fluid of OA patients, and its expression was negatively correlated with the severity of OA.展开更多
BACKGROUND： The detection of differential gene expression in brain is possible by cDNA microarray technology, and the screening of differentially expressed genes might provide a biological basis for gene-targeted the...BACKGROUND： The detection of differential gene expression in brain is possible by cDNA microarray technology, and the screening of differentially expressed genes might provide a biological basis for gene-targeted therapy for tumors. OBJECTIVE： To detect the differential expression of genes among astrocytoma SHG-44 （WHO grade Ⅳ）, CHG-5 （WHO grade Ⅱ）, and ATRA-treated SHG-44 cell lines by cDNA microarray. DESIGN： Laboratory experiments in vitro. SETTING： Department of Neurobiology, the Third Military Medical University. MATERIALS： The experiment was performed at the Department of Neurobiology in the Third Military Medical University of the Chinese PLA from January to October 2007. The SHG-44 cell line （WHO grade Ⅳ） was established by Prof. Ziwei Du, and the CHG-5 cell line （WHO grade Ⅱ） was set up by Prof. Xiuwu Bian from the Third Military Medical University of the Chinese PLA. The cDNA microarray containing 9182 known genes was prepared and provided by Dr. Yang Zhong at the City University of Hong Kong. METHODS： To screen differentially expressed genes from the gene expression profiles detected by cDNA microarray comparisons were made between CHG-5 and SHG-44 cells and between SHG-44 cells with or without treatment with 10 μmol/L ATRA. Some differentially expressed genes were selected randomly for Northern Blot analysis to confirm the results of the microarray. The determination criteria for differential gene expression were as follows. ① The ratio of Cy5 signal to Cy3 was greater than 2.0 or less than 0.5. ② The results of the triplicate microarray hybridizations showed the same trend in three experiments. ③ A gene appeared at least two times on the triplicate microarray hybridizations, and the 3^rd value did not show a contradictory trend. A normalized ratio of Cy5 intensity to Cy3 greater than 2.0 or less than 0.5 was considered to represent up-regulated or down-regulated gene expression, respectively. MAIN OUTCOME MEASURES： The identification of genes that were similarly regulated （overlapping） during tumor progression and differentiation, by comparison of gene expression profiles between CHG-5 and SHG-44 cells, and between SHG-44 cells with or without treatment with ATRA. RESULTS： Thirty-one overlapping genes were found to have similar regulatory effects on astrocytomas; among them, twenty genes were up-regulated and eleven were down-regulated in both comparisons between CHG-5 and SHG-44 cells, and between SHG-44 cells with or without treatment with ATRA. The four reported genes, SERPINFI, MAPKI 1, HIFIA and SOD2, were up-regulated in this study. CONCLUSION： The differentially expressed genes in different grade astrocytoma cell lines were revealed primarily by cDNA microarray; among them, five identified overlapping genes, SERPINF1, MAPK11, DCTN2, HIF1 A and SOD2, were related to the malignant progression of astrocytoma cells.展开更多
Osteoarthritis(OA)is a prevalent degenerative joint disease characterized by cartilage loss and accounts for a major source of pain and disability worldwide.However,effective strategies for cartilage repair are lackin...Osteoarthritis(OA)is a prevalent degenerative joint disease characterized by cartilage loss and accounts for a major source of pain and disability worldwide.However,effective strategies for cartilage repair are lacking,and patients with advanced OA usually need joint replacement.Better comprehending OA pathogenesis may lead to transformative therapeutics.Recently studies have reported that exosomes act as a new means of cell-to-cell communication by delivering multiple bioactive molecules to create a particular microenvironment that tunes cartilage behavior.Specifically,exosome cargos,such as noncoding RNAs(ncRNAs)and proteins,play a crucial role in OA progression by regulating the proliferation,apoptosis,autophagy,and inflammatory response of joint cells,rendering them promising candidates for OA monitoring and treatment.This review systematically summarizes the current insight regarding the biogenesis and function of exosomes and their potential as therapeutic tools targeting cell-to-cell communication in OA,suggesting new realms to improve OA management.展开更多
AIM To assess whether elevated serum carcinoembryonic antigen(CEA) is in the inferior prognosis for pathological lymph node-negative(p N_0) gastric cancer(GC) patients who underwent D_2 gastrectomy.METHODS About 469 p...AIM To assess whether elevated serum carcinoembryonic antigen(CEA) is in the inferior prognosis for pathological lymph node-negative(p N_0) gastric cancer(GC) patients who underwent D_2 gastrectomy.METHODS About 469 p N0 GC patients,who received D^2 radical gastrectomy were retrospectively analyzed. The X-tile plots cut-off point for CEA were 30.02 ng/m L using minimum P-value from log-rank χ~2 statistics,and p N_0 GC patients were assigned to two groups: those more than 30.02 ng/m L(n = 48;CEA-high group) and those less than 30.02 ng/m L(n = 421;CEA-low group). Clinicopathologic characteristics were compared usingPearson's χ2 or Fisher's exact tests,and survival curves were so manufactured using the Kaplan-Meier method. Univariate and multivariate analysis were carried out using the logistic regression method.RESULTS The percentage of vessel carcinoma embolus(31.35% vs 17.1%) and advanced GC(T_(2-4b))(81.25% vs 65.32%) were higher in CEA-high group than CEA-low group. The CEA-positive patients had a significantly poorer prognosis than the CEA-nagetive patients in terms of overall survival(57.74% vs 90.69%,P < 0.05),and no different was found between subgroup of T category,differentiation,nerve invasion,and vessel carcinoma embolus(all P > 0.05). Multivariate survival analysis showed that CEA(OR = 4.924),and T category(OR = 2.214) were significant prognostic factors for stage p N0 GC(all P < 0.05). Besides,only T category(OR = 1.962) was an independent hazard factor in the CEA-high group(P < 0.05).CONCLUSION Those pretreatment serum CEA levels over 30.02 ng/m L on behalf of worse characteristics and unfavourable tumor behavior,and a poor prognosis for a nearly doubled risk of mortality in GC patients.展开更多
AIM:To detect human papillomavirus(HPV) DNA in esophageal carcinoma(EC) 109 cells and investigate the relationship between HPV and EC.METHODS:Genomic DNA and total RNA from EC109 cells were isolated.HPV DNA was detect...AIM:To detect human papillomavirus(HPV) DNA in esophageal carcinoma(EC) 109 cells and investigate the relationship between HPV and EC.METHODS:Genomic DNA and total RNA from EC109 cells were isolated.HPV DNA was detected by polymerase chain reaction(PCR) with the general primer sets of My09/11 and GP5 +/6 + for the HPV L1 gene and type-specific primer sets for HPV18 E6 and HPV18 E6-E7.Reverse transcription(RT) of mRNA isolated from EC109 cells was performed to produce a cDNA.And then a PCR-based protocol for the amplification of papillomavirus oncogene transcripts was used to analyze HPV18 DNA and integrated transcripts of HPV18 in the chromosomes of EC109 cells.The final nested PCR products were cloned into a pMD-18T vector and sequenced to analyze the chromosomal location of HPV integration.RESULTS:HPV18 DNA was detected in EC109 cells by PCR using the general primer sets of My09/11 and GP5 +/6 + for HPV L1 and the type-specif ic primer sets for HPV18 E6 and E6-E7 to generate products of 450 bp,150 bp,335 bp and 944 bp,respectively.Approximately 600 bp of integrated HPV18-specific transcript was identified.The final nested PCR product of integrated HPV18 DNA was cloned into a pMD-18T vector and sequenced to analyze the chromosomal location of HPV integration.Sequence alignment showed that the HPV18 sequence from EC109 cells was identical to that of the encoded early protein E7-E1 of the standard HPV18 strain X05015,and another partial gene sequence was identical to a partial sequence of human chromosome 8.CONCLUSION:Integration of the HPV genome into the host cell chromosome suggests that persistent HPV infection is vital for malignant cell transformation and carcinogenesis.展开更多
基金financial support from the National Key Research and Development Program(Grant No.2024YFA1209801)the National Natural Science Foundation of China(Grant Nos.12302140,12325204)+4 种基金the China Postdoctoral Science Foundation(Grant No.2023M732794)the Fundamental Research Funds for the Central Universities of China(Grant No.sxzy012023213)the Scientific Research Program of Shaanxi Province(Grant No.2023JC-XJ-02)the Young Talent Support Program of Xi'an Science and Technology Association(Grant No.959202413069)Postdoctoral Fellowship Program(Grade B)of China Postdoctoral Science Foundation(Grant No.GZB20230575)。
文摘Hypervelocity rocket sled systems are critical for testing advanced military technologies,yet track damage at speeds exceeding Mach 5 remains a significant challenge for system reliability and performance.In this study,we investigated the hypervelocity impact response and protection for highstrength U71 Mn or bainitic steel used in rocket sled tracks.Flyer plate impact experiments using a two-stage light-gas gun were conducted to study the hypervelocity collision response,followed by the microstructural characterization via optical microscope,scanning electron microscopy equipped with electron backscatter diffraction to reveal underlying damage mechanisms.Then,the calibrated thermalmechanical coupled finite element simulations using the Johnson-Cook constitutive model and MieGrüneisen equation of state were carried out.Results indicated that bainitic steel exhibits superior impact resistance with predominantly smooth scratch-dominated damage due to its higher ductility.In contrast,U71 Mn suffered significant material spallation and crack propagation arising from brittle fracture mechanisms.Zinc-rich epoxy primer coatings effectively mitigated stress concentration and temperature rise in the substrate at impacting velocities below 2.4 km/s,so as to suppress the microstructural damage such as adiabatic shear bands and dynamic recrystallization.However,coating protection diminished at ultra-high-speed impacts due to the coating failure.Dimensional analysis established quantitative relationships of the gouge damage size to projectile mass,impact velocity,and material yield strength.This study provides in-depth insights into damage mechanisms in hypervelocity rail systems,demonstrating that bainitic steel combined with protective coatings can significantly enhance impact resistance and system reliability,offering valuable guidance for the design and optimization of hypervelocity testing platforms.
基金supported in part by the National Science Fund for Distinguished Young Scholars under Grant (42025403)the National Key Research and Development Plan of China (2021YFA0716800)the National Key Research and Development Plan of China (2022YFC2903804)。
文摘The increasing risk of ground pressure disasters resulting from deep well mining highlights the urgent need for advanced monitoring and early warning systems.Ground pressure monitoring,supported by microseismic technology,plays a pivotal role in ensuring mine safety by enabling real-time identifi cation and accurate classification of vibration signals such as microseismic signals,blasting signals,and noise.These classifications are critical for improving the efficacy of ground pressure monitoring systems,conducting stability analyses of deep rock masses,and implementing timely and precise roadway support measures.Such eff orts are essential for mitigating ground pressure disasters and ensuring safe mining operations.This study proposes an artificial intelligence-based automatic classification network model for mine vibration signals.Based on conventional convolutional neural networks,the proposed model further incorporates long short-term memory(LSTM)networks and attention mechanisms.The LSTM component eff ectively captures temporal correlations in time-series mining vibration data,while the attention mechanism enhances the models’ability to focus on critical features within the data.To validate the eff ectiveness of our proposed model,a dataset comprising 480,526 waveform records collected in 2022 by the microseismic monitoring system at Guangxi Shanhu Tungsten Mine was used for training,validation,and testing purposes.Results demonstrate that the proposed artifi cial intelligence-based classifi cation method achieves a higher recognition accuracy of 92.21%,significantly outperforming traditional manual classification methods.The proposed model represents a signifi cant advancement in ground pressure monitoring and disaster mitigation.
文摘The electrocatalytic urea oxidation reaction(UOR)has emerged as an energy-efficient alternative to the traditional oxygen evolution reaction for hydrogen production,with mechanistic understanding being critical for the rational design of catalysts.This review systematically summarizes recent advances in in situ characterization techniques for elucidating the dynamic reaction mechanisms of UOR.Studies reveal that phase transitions,valence state migration,and electronic structure evolution of catalysts under operational conditions are key factors governing activity and stability.Techniques such as in situ X-ray diffraction,X-ray absorption spectroscopy,Raman spectroscopy,and Fourier-transform infrared spectroscopy enable real-time monitoring of catalyst reconstruction,intermediate evolution,and interfacial adsorption behavior,overcoming the environmental deviations inherent in conventional ex situ characterization.When combined with theoretical calculations,these methods provide direct evidence for identifying active-site configurations,reaction pathways,and rate-determining steps.In addition,special emphasis is placed on multimodal in situ strategies for deciphering synergistic effects in nickel-based catalysts,while current challenges,including non-alkaline systems,real wastewater environments,and multi-metal cooperation mechanisms,are critically discussed.Future research should focus on developing novel in situ approaches for complex systems and establishing a mutually reinforcing framework integrating theoretical prediction and experimental validation,thereby advancing UOR catalyst design from empirical exploration to mechanism-guided optimization.
文摘Objective:To analyze the risk of osteoporosis among middle-aged men in the cold regions of China(Heilongjiang Province)and provide theoretical support for the early identification of high-risk populations.Methods:Bone mineral density(BMD)data were collected from male subjects aged 50-65 who met the inclusion criteria at the physical examination center of a hospital in Harbin between August to December 2022.General clinical data and dietary information were obtained through face-to-face interviews using a dietary questionnaire survey.Results:The prevalence of osteoporosis and osteopenia was 14.38%and 52.06%,respectively,while normal bone mass accounted for 33.56%.Significant differences were observed among groups in smoking habits,sunlight exposure,exercise levels,and dietary patterns at each bone mass level.The BMD of the lumbar spine,femoral neck,and hip showed a negative correlation with the Dietary Inflammatory Index(DII)score.Multivariate logistic regression analysis revealed that smoking and a diet high in oil and salt were positively associated with the risk of osteoporosis.A pro-inflammatory diet was also positively correlated with osteoporosis risk,with individuals in this group being 7.723 times more likely to develop osteoporosis compared to those in the anti-inflammatory diet group.Conclusion:The high prevalence of osteoporosis and osteopenia observed in this study highlighted that osteoporosis is a significant and pressing issue among middle-aged men.Smoking,limited sunlight exposure,reduced physical activity,diets high in oil and salt,and pro-inflammatory diets were identified as major risk factors for bone loss.These factors are closely linked to the geography,climate,and cultural practices of cold regions in China.Primary healthcare in this region should focus on the screening and prevention of osteoporosis in middle-aged men by promoting smoking cessation,increased sunlight exposure,adequate vitamin D supplementation,regular physical activity,and adherence to a healthy diet to maintain bone health.
基金Supported by The Chongqing Talents Project,No.cstc2021ycjh-bgzxm0150The First Batch of Key Disciplines on Public Health in Chongqing,The Health Commission of Chongqing,No.2022(72)+1 种基金The Remarkable Innovation-Clinical Research Project,The Second Affiliated Hospital of Chongqing Medical UniversityThe Scientific and Technological Research Program of Chongqing Municipal Education Commission,the Second Affiliated Hospital of Chongqing Medical University,No.KJZD-K202300404.
文摘Hepatitis B virus(HBV)infection is a global health concern.The current sequen-tial endpoints for the treatment of HBV infection include viral suppression,hepatitis B e antigen(HBeAg)seroconversion,functional cure,and covalently closed circular DNA(cccDNA)clearance.Serum hepatitis B core-related antigen(HBcrAg)is an emerging HBV marker comprising three components:HBeAg,hepatitis B core antigen,and p22cr.It responds well to the transcriptional activity of cccDNA in the patient's liver and is a promising alternative marker for serolo-gical testing.There is a strong correlation,and a decrease in its level corresponds to sustained viral suppression.In patients with chronic hepatitis B(CHB),serum HBcrAg levels are good predictors of HBeAg seroconversion(both spontaneous and after antiviral therapy),particularly in HBeAg-positive patients.Both low baseline HBcrAg levels and decreasing levels early in antiviral therapy favored HBsAg seroconversion,which may serve as a good surrogate option for treatment endpoints.In this review,we summarize the role of serum HBcrAg in the treat-ment of CHB.Therefore,long-term continuous monitoring of serum HBcrAg levels contributes to the clinical management of patients with CHB and optimizes the choice of treatment regimen,making it a promising marker for monitoring HBV cure.
基金financially supported by the National Natural Science Foundation of China(Grant No.42377321)。
文摘Cropland is persistently affected by soil loss by water erosion in China,which causes economic loss and threatens soil health.Integrating crop switching and improved management provides a promising strategy for controlling soil loss by water erosion in cropland and promoting sustainable agriculture.However,optimizing crop composition with fewer inputs involves balancing agricultural resource use with environmental costs.Aiming to explore the potential of crop switching as a strategy for mitigating soil erosion in cropland,we develop a spatial optimization model that redistributes the sown areas of different crops in each prefecture-level city based on existing resource availability.Our findings gained from our simulations show that crop switching in China alone can reduce total soil erosion in cropland by an estimated 13%.Furthermore,combining crop switching with improved agricultural management practices can further reduce soil erosion in cropland by an estimated 25%.Cereals including maize,wheat,and rice demonstrate significant potential for reducing soil erosion in cropland.Shifting major maize-producing areas northward could result in a substantial decrease in soil erosion,ranging from 10% to 19% of historical soil erosion in cropland.These results offer implications for formulating regional strategy in mitigating soil erosion challenges in China while maximizing the benefits from existing agricultural resource.
基金financially supported by National Natural Science Foundation of China(No.52072410).
文摘Bubbles are prevalent defects on the oxidized surfaces of ultra-high temperature carbides,compromis-ing structural stability and oxidation resistance.Despite their significance,the formation mechanisms and microstructural evolution of bubbles during ultra-high temperature oxidation remain inadequately understood.To address this gap,the bubble behaviors of multicomponent carbides,including(Hf,Ti)C,(Hf,Zr,Ti)C,(Hf,Zr,Ti,Ta)C,and(Hf,Zr,Ti,Nb)C,were investigated under oxidation conditions at 2500℃.The roles of various elements were elucidated through first-principles calculations.Results show that the for-mation of a dense composite oxide layer is essential for bubble generation,with the release of gaseous products serving as the primary driving force.The microstructure of the bubbles is influenced by the ma-trix composition.The addition of Ti,Ta,and Nb significantly lowers the surface energy of the shell oxides,providing preferential nucleation sites for bubbles.The progressive oxidation of Ti leads to the formation of a“TiO_(2)-TiO-HfO_(2)”multilayerstructureat thebubbletop,which evolvesintoadendriticstructurewith prolonged oxidation.Ta and Nb further modulate the size and number of bubbles by altering the compo-sition and surface energy of the shell oxides.
文摘BACKGROUND The incidence of hypertriglyceridemic acute pancreatitis(HTG-AP)has increased yearly,but updated population-based estimates on the incidence of HTG-AP are lacking.Reducing serum triglyceride(TG)levels quickly is crucial in the early treatment of HTG-AP.Decreased serum TG levels are treated by non-invasive methods,which include anti-lipidemic agents,heparin,low-molecular weight heparin,and insulin,and invasive methods,such as blood purification including hemoperfusion(HP),plasmapheresis,and continuous renal replacement therapy.However,authoritative guidelines have not been established.Early selection of appropriate treatment is important and beneficial in controlling the development of HTG-AP.AIM To evaluate the effect between patients treated with intravenous insulin(INS)and HP to guide clinical treatment.METHODS We retrospectively reviewed 371 patients with HTG-AP enrolled in the Department of Fujian Provincial Hospital form April 2012 to March 2021.The inpatient medical and radiologic records were reviewed to determine clinical features,severity,complications,mortality,recurrence rate,and treatment.Multivariate logistic regression analyses were used to analyze risk factors for severe HTG-AP.Propensity score matching was used to compare the clinical outcomes of INS and HP.RESULTS A total of 371 patients met the HTG-AP criteria.The incidence of HTG-AP was increased by approximately 2.6 times during the 10 years(8.4%in April 2012-March 2013 and 22.3%in April 2020-March 2021).The highest incidence rate of acute pancreatitis was observed for men in the age group of 30-39 years.The amylase level was elevated in 80.1%of patients but was only three times the normal value in 46.9%of patients.The frequency of severe acute pancreatitis(26.9%),organ failure(31.5%),rate of recurrence(32.9%),and mortality(3.0%)of HTG-AP was high.Improved Marshall score,modified computed tomography severity index score,baseline TG,baseline amylase,C-reactive protein(CRP),albumin,aspartate aminotransferase,low-density lipoprotein cholesterol,urea nitrogen,creatinine,calcium,hemoglobin,free triiodothyronine,admission to intensive care unit,and mortality were significantly different between patients with different grades of severity(P<0.050).Multivariate logistic regression analysis confirmed that high CRP[P=0.005,odds ratio(OR)=1.011,95%CI:1.003-1.019],low calcium(P=0.003,OR=0.016,95%CI:0.001-0.239),and low albumin(P=0.023,OR=0.821,95%CI:0.693-0.973)were risk factors of severe HTG-AP.After propensity score matching adjusted by sex,age,severity of HTG-AP,and baseline TG,the serum TG significantly decreased in patients treated with INS(P<0.000)and HP(P<0.000)within 48 h.However,the clearance rate of TG(57.24±33.70%vs 56.38±33.61%,P=0.927)and length of stay(13.04±7.92 d vs 12.35±6.40 d,P=0.730)did not differ between the two groups.CONCLUSION The incidence of HTG-AP exhibited a significant increase,remarkable severity,and recurrent trend.Patients with mild and moderately severe acute pancreatitis can be treated effectively with INS safely and effectively without HP.
文摘AIM:To investigate the relationship between human papillomavirus(HPV)infection and concurrent esophagus and gastric cardia cancer from the same patient(CC)and examine the significance of P16 INK4A protein expression.METHODS:Polymerase chain reaction was used to detect the presence of HPV type16(HPV16).The expression of P16 INK4A protein was detected using immunohistochemistry.RESULTS:Among the CC specimens,HPV16-DNA was found in eight cases of esophageal squamous cell carcinoma(ESCC)and five cases of gastric cardia adenocarcinoma(GCA),respectively(47%vs 29%),and two of both ESCC and GCA.P16 INK4A was highly expressed in both ESCC and GCA.In the HPV-associated positive CC,higher P16 INK4A expression was observed in the GCA than in the ESCC(75%vs 25%,P<0.05).CONCLUSION:HPV16 as a correlated risk factor may play an important role in the development of ESCC and GCA.P16 INK4A may be a screening index in the HPVassociated carcinoma of gastric cardia.
文摘The basal levels of magnesium and copper in rat brain and flowering plum fruit dialysates, and the background concentration of calcium in pea dialysates have been determined with sensitive spectroscopic techniques including atomic absorption spectrometry and spectrophotometry based on amino G acid chlorophosphonazo. It is found that the magnesium level in flowering plum fruit dialysates is much lower than that in rat brain dialysates, indicating a considerable composition difference present between a plant dialysate and an animal one.
基金Supported by the National Natural Science Foundation of China(No.81672219No.81601936)the Science and Technology Support Program of Sichuan province(No.2014SZ0023-2)
文摘Objective To investigate the expression of miRNA-140 in chondrocytes and synovial fluid of osteoarthritis(OA) patients, and explore the relationship between the miRNA-140 expression and OA severity. Methods This study enrolled 30 OA patients who underwent total knee arthroplasty for chondrocytes sampling and 30 OA patients who underwent intra-articular injection for synovial fluid sampling. All OA patients were grouped into mild [Kellgren and Lawrence(KL) grade 1-2], moderate(KL grade 3) and severe(KL grade 4), with 10 in each subgroups for each sampling purposes. 7 non-OA patients and 10 patients with knee injury were collected for cartilage and synovial fluid sampling respectively as control groups. Chondrocytes were isolated from the cartilage tissue and cultured in vitro. Quantitative real time PCR for miRNA-140 in chondrocytes and synovial fluid were performed, and the U6 sn RNA was used as internal control. The expression difference of miRNA-140 among groups and correlation between the expression and the KL grade of OA were analysed using one-way ANOVA and Spearman test respectively. Results The expression of miRNA-140 in chondrocytes of knees in OA patients was reduced than that in normal knees, and the between-group difference was statistically significant(F=305.464, P<0.001). miRNA-140 could be detected in synovial fluid of both normal knees and OA knees, its relative expression level was reduced in synovial fluid of OA group compared with normal group, and the between-group difference was statistically significant as well(F=314.245, P<0.001). The relative expression level of miRNA-140 in both chondrocytes and synovial fluid were negatively correlated with the KL grade of OA(r=-0.969, P<0.001; r=-0.970, P<0.001). Conclusion miRNA-140 could be detected in chondrocytes and synovial fluid of OA patients, and its expression was negatively correlated with the severity of OA.
基金ScientificResearch Foundation from Health Bareau of Sichuan Province, No.050209
文摘BACKGROUND： The detection of differential gene expression in brain is possible by cDNA microarray technology, and the screening of differentially expressed genes might provide a biological basis for gene-targeted therapy for tumors. OBJECTIVE： To detect the differential expression of genes among astrocytoma SHG-44 （WHO grade Ⅳ）, CHG-5 （WHO grade Ⅱ）, and ATRA-treated SHG-44 cell lines by cDNA microarray. DESIGN： Laboratory experiments in vitro. SETTING： Department of Neurobiology, the Third Military Medical University. MATERIALS： The experiment was performed at the Department of Neurobiology in the Third Military Medical University of the Chinese PLA from January to October 2007. The SHG-44 cell line （WHO grade Ⅳ） was established by Prof. Ziwei Du, and the CHG-5 cell line （WHO grade Ⅱ） was set up by Prof. Xiuwu Bian from the Third Military Medical University of the Chinese PLA. The cDNA microarray containing 9182 known genes was prepared and provided by Dr. Yang Zhong at the City University of Hong Kong. METHODS： To screen differentially expressed genes from the gene expression profiles detected by cDNA microarray comparisons were made between CHG-5 and SHG-44 cells and between SHG-44 cells with or without treatment with 10 μmol/L ATRA. Some differentially expressed genes were selected randomly for Northern Blot analysis to confirm the results of the microarray. The determination criteria for differential gene expression were as follows. ① The ratio of Cy5 signal to Cy3 was greater than 2.0 or less than 0.5. ② The results of the triplicate microarray hybridizations showed the same trend in three experiments. ③ A gene appeared at least two times on the triplicate microarray hybridizations, and the 3^rd value did not show a contradictory trend. A normalized ratio of Cy5 intensity to Cy3 greater than 2.0 or less than 0.5 was considered to represent up-regulated or down-regulated gene expression, respectively. MAIN OUTCOME MEASURES： The identification of genes that were similarly regulated （overlapping） during tumor progression and differentiation, by comparison of gene expression profiles between CHG-5 and SHG-44 cells, and between SHG-44 cells with or without treatment with ATRA. RESULTS： Thirty-one overlapping genes were found to have similar regulatory effects on astrocytomas; among them, twenty genes were up-regulated and eleven were down-regulated in both comparisons between CHG-5 and SHG-44 cells, and between SHG-44 cells with or without treatment with ATRA. The four reported genes, SERPINFI, MAPKI 1, HIFIA and SOD2, were up-regulated in this study. CONCLUSION： The differentially expressed genes in different grade astrocytoma cell lines were revealed primarily by cDNA microarray; among them, five identified overlapping genes, SERPINF1, MAPK11, DCTN2, HIF1 A and SOD2, were related to the malignant progression of astrocytoma cells.
基金funded by the National Natural Science Foundation of China(No.81974347)the Science and Technology Program of Sichuan Province(No.2021YJ0444)+1 种基金China Postdoctoral Science Foundation(No.2021M702351)Post-Doctor Research Project,West China Hospital,Sichuan University(No.2020HXBH081)。
文摘Osteoarthritis(OA)is a prevalent degenerative joint disease characterized by cartilage loss and accounts for a major source of pain and disability worldwide.However,effective strategies for cartilage repair are lacking,and patients with advanced OA usually need joint replacement.Better comprehending OA pathogenesis may lead to transformative therapeutics.Recently studies have reported that exosomes act as a new means of cell-to-cell communication by delivering multiple bioactive molecules to create a particular microenvironment that tunes cartilage behavior.Specifically,exosome cargos,such as noncoding RNAs(ncRNAs)and proteins,play a crucial role in OA progression by regulating the proliferation,apoptosis,autophagy,and inflammatory response of joint cells,rendering them promising candidates for OA monitoring and treatment.This review systematically summarizes the current insight regarding the biogenesis and function of exosomes and their potential as therapeutic tools targeting cell-to-cell communication in OA,suggesting new realms to improve OA management.
基金Supported by Domestic Support from Young and Middle-aged key personnel Training program for provincial Health planning Students,No.2017-ZQN-18provincial Youth Health Science Research project,No.2014-2-8 and No.2017-1-13National key Clinical Specialty Construction project,No.2013-2016
文摘AIM To assess whether elevated serum carcinoembryonic antigen(CEA) is in the inferior prognosis for pathological lymph node-negative(p N_0) gastric cancer(GC) patients who underwent D_2 gastrectomy.METHODS About 469 p N0 GC patients,who received D^2 radical gastrectomy were retrospectively analyzed. The X-tile plots cut-off point for CEA were 30.02 ng/m L using minimum P-value from log-rank χ~2 statistics,and p N_0 GC patients were assigned to two groups: those more than 30.02 ng/m L(n = 48;CEA-high group) and those less than 30.02 ng/m L(n = 421;CEA-low group). Clinicopathologic characteristics were compared usingPearson's χ2 or Fisher's exact tests,and survival curves were so manufactured using the Kaplan-Meier method. Univariate and multivariate analysis were carried out using the logistic regression method.RESULTS The percentage of vessel carcinoma embolus(31.35% vs 17.1%) and advanced GC(T_(2-4b))(81.25% vs 65.32%) were higher in CEA-high group than CEA-low group. The CEA-positive patients had a significantly poorer prognosis than the CEA-nagetive patients in terms of overall survival(57.74% vs 90.69%,P < 0.05),and no different was found between subgroup of T category,differentiation,nerve invasion,and vessel carcinoma embolus(all P > 0.05). Multivariate survival analysis showed that CEA(OR = 4.924),and T category(OR = 2.214) were significant prognostic factors for stage p N0 GC(all P < 0.05). Besides,only T category(OR = 1.962) was an independent hazard factor in the CEA-high group(P < 0.05).CONCLUSION Those pretreatment serum CEA levels over 30.02 ng/m L on behalf of worse characteristics and unfavourable tumor behavior,and a poor prognosis for a nearly doubled risk of mortality in GC patients.
基金Supported by An independent research fund from the National Institute for Viral Disease Control and Prevention,the Chinese Center for Disease Control and Preventionthe State Key Laboratory for Infectious Disease Prevention and Control (Grant No. 2011SKLID103)
文摘AIM:To detect human papillomavirus(HPV) DNA in esophageal carcinoma(EC) 109 cells and investigate the relationship between HPV and EC.METHODS:Genomic DNA and total RNA from EC109 cells were isolated.HPV DNA was detected by polymerase chain reaction(PCR) with the general primer sets of My09/11 and GP5 +/6 + for the HPV L1 gene and type-specific primer sets for HPV18 E6 and HPV18 E6-E7.Reverse transcription(RT) of mRNA isolated from EC109 cells was performed to produce a cDNA.And then a PCR-based protocol for the amplification of papillomavirus oncogene transcripts was used to analyze HPV18 DNA and integrated transcripts of HPV18 in the chromosomes of EC109 cells.The final nested PCR products were cloned into a pMD-18T vector and sequenced to analyze the chromosomal location of HPV integration.RESULTS:HPV18 DNA was detected in EC109 cells by PCR using the general primer sets of My09/11 and GP5 +/6 + for HPV L1 and the type-specif ic primer sets for HPV18 E6 and E6-E7 to generate products of 450 bp,150 bp,335 bp and 944 bp,respectively.Approximately 600 bp of integrated HPV18-specific transcript was identified.The final nested PCR product of integrated HPV18 DNA was cloned into a pMD-18T vector and sequenced to analyze the chromosomal location of HPV integration.Sequence alignment showed that the HPV18 sequence from EC109 cells was identical to that of the encoded early protein E7-E1 of the standard HPV18 strain X05015,and another partial gene sequence was identical to a partial sequence of human chromosome 8.CONCLUSION:Integration of the HPV genome into the host cell chromosome suggests that persistent HPV infection is vital for malignant cell transformation and carcinogenesis.
